Snow thrower



g- 6, 1968 e. KLAPPRODT 3,395,466

SNOW THROWER Filed June 28, 1965 Gl Qdlczppr-od? 4 44% Way 0M CflTToRMEX/ United States Patent 3,395,466 SNOW THROWER Glen Klapprodt, Mount Morris, Ill. 61054 Filed June 28, 1965, Ser. No. 467,353 4 Claims. (Cl. 37-43) ABSTRACT OF THE DISCLOSURE A snow plow having part cylindrical scoop with an open front end and carrying an elongated impeller supported for rotation about a horizontal transverse axis. The impeller comprises two conical body sections tapering toward the center,.two helical blades wrapped around the body sections and similarly tapering in outside diameter toward the center, and a central blower formed by radial paddles on opposite sides of a central disk. When the impeller is driven through a drive mechanism on the scoop, the helical blades throw snow axially of the impeller, leaving the snow in free flight toward the blower, from which the snow is discharged through a central spout.

This invention relates generally to excavating machines and, more particularly, to snow plows for collecting snow or other fluent material from a path to be cleared and throwing the collected snow to an out-of-the-way position along side of the path or into a vehicle to be hauled away. Known machines of the general type with which the invention is concerned are shown in Patents Nos. 2,419,779 and 3,086,304. In such machines, auger-type conveyors are mounted in an open-ended scoop to carry the snow entering the scoop into a blower, mounted either at the center of the auger or at one end, and operable to throw the snow upward out of the scoop.

The general object of the present invention is to improve on known snow throwers by substantially reducing the power required to handle a given volume of snow.

Another object is to provide a novel snow thrower capable of handling a substantially greater volume of snow with a given power input as a result of the more efficient feeding of the snow into the blower.

A related object is to obtain optimum available power at the blower by reducing the power required to feed snow into the blower.

The invention also resides in the novel configuration of the auger-type impeller.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings, in which:

FIGURE 1 is a fragmentary perspective view of a snow thrower embodying the novel features of the present invention.

FIG. 2 is a somewhat enlarged cross-sectional view taken substantially along the line 2-2 of FIG. 1.

FIG. 3 is a fragmentary cross-section taken along the line 3-3 of FIG. 2.

As shown in the drawings for purposes of illustration, the invention is embodied in a snow thrower adapted to be mounted on the front of a truck or tractor (not shown) and pushed along a path to be cleared of snow. For this purpose, the thrower comprises a frame 11 in the form of an open-ended scoop defined by a generally semi-cylindrical sheet metal shell 12 forming the top and rear walls of the scoop and closed at its opposite ends by laterally spaced upright side walls 13. The open front end of the scoop is defined by the free lower edge 14 of the shell which forms a scraper movable along the surface 15 to be cleared, and by three outwardly flaring collecting plates 17 and 18 extending across the top of the opening along the upper edge of the shell and down the leading edges of the side walls 13. .To support the scoop for move- 3,395,466 Patented Aug. 6, 1968 ICC ment along the surface 15, skids 19 preferably are provided beneath the side walls with upwardly and forwardly inclined leading end portions 20.

Supported within the scoop 11 is an auger-type impeller 21 which extends between the side walls 13 and is mounted on a horizontal shaft 22 journaled at its opposite ends in the side walls for rotation about an axis 23 extending transversely of the path of movement of the machine during operation and preferably perpendicular to the path. While the impeller may be constructed to feed snow toward one side of the scoop, the blades 24 and 25 thereof on opposite sides of the longitudinal center of the impeller preferably are oppositely pitched and rotated in a direction to feed the snow from both sides toward the center, particularly in larger sized snow throwers for clearing relatively wide paths.

Collected snow is discharged from the scoop 11 by a blower located between the two blades 24 and 25 and having open sides for receiving snow. In this instance, the blower is formed by two groups of generally rectangular blades or paddles 27 angularly spaced around the body of the impeller on opposite sides of a central disk 28 in a plane perpendicular to the axis 23 and dividing the impeller in half, each paddle being secured at its inner end to the impeller for rotation with the impeller and projecting radially outwardly therefrom, and connected along one side to the central disk. The free corners of the paddles of each group are connected by narrow reinforcing rings 29 encircling the blower and defining the open sides of the latter.

Extending upwardly from the shell 12 above an opening 30 (FIG. 2) alined with the blower is a tubular spout 31 which defines a discharge passage generally tangent to the paths of the blower paddles for receiving the snow thrown off by the blower and carrying the snow out of the scoop. A deflector (not shown) usually is provided at the upper end of the spout for directing the discharged snow toward one side of the path. The paddles preferably are disposed in planes that are inclined a few degrees out of parallel with the plane of the shaft axis as shown at 27 in FIG. 3 to incline the discharged snow slightly toward the disk 28 and toward the center of the spout.

Herein, the impeller 21 and the blower paddles 27 thereon are rotated about the impeller axis 23 by an endless chain 32 trained around a sprocket wheel 33 on one end of the shaft 22 and a second sprocket wheel 34 on the parallel output shaft 35 of a drive mechanism housed in a casing 37 herein mounted on top of the shell 12. This drive mechanism may take the form of a motor and gearmg (not shown) connecting the motor to the output shaft, or it may be a drive adapted to be connected to a power source on the propelling vehicle.

In accordance with the present invention, the impeller blades 24 and 25 are formed with progressively decreasing outside diameters tapering from the side walls 13 of the scoop 11 toward the blower, and are rotated at high speed to shave off snow entering the scoop and throw the snow axially toward and into the blower. With this arrangement, it has been demonstrated that a substantial power advantage is obtained, apparently because the generally conical blades contact the snow only once and impart to the snow the necessary velocity to carry it into the blower, thereby eliminating the power losses that have resulted in prior snow throwers in the conveying of confined snow between adjacent convolutions of an auger flight having a substantially constant outside diameter.

As shown most clearly in FIG. 3, the impeller body is formed as two frusto-conical sections 38 and 39 tapering toward the center of the impeller and suitably joined together at their smaller ends. The blades 24 and 25 herein are of uniform radial width and may be relatively narrow as compared with prior auger-type impellers due to the fact that they are not required to push large quantities of snow slowly along the impeller. Instead, each blade shaves off a smaller quantity of snow (depending, of course, on the rate of advance and the depth of the snow entering the scoop) and kicks the snow quickly into the blower. As will be seen in FIGS. 2 and 3, the taper of the body and the radial width of the blades are correlated to space each successive convolution of the blade, from the larger end of the section 38, 39 toward the smaller end, radially inwardly from the corresponding portions of the preceding convolution, and preferably to make the outside daimeter of each successive convolution even with or slightly inside the base or root diameter of the corresponding portion of the preceding convolution.

In the illustrative blower, the blades 24 and 25 are 1 /2 pitch screws, that is, each blade turns around the associated section 1 /2 times. In a highway machine, the impeller is rotated at no-load speeds on the order of 400 to 600 r.p.m. with a power source preferably capable of developing 100 horsepower or more and maintaining a rate or rotation under full load conditions of 300 to 400 r.p.m. or more.

With the impeller 21 rotating in the direction indicated by the arrows in the drawings, the scoop 11 is advanced :along the path to be cleared at a speed commensurate with the depth of the snow. Upon entering the front of the scoop, the snow is fed into the impeller, either from the front of or upwardly into the underside of the impeller, and into the path of one of the helical blades 24, 25. Of course, the rotation of the impeller produces an apparent lateral motion of the screw-like blades at rate corresponding to the rate of rotation. If one pitch or full convolution of the blades extends approximately two feet along the body section, the apparent lateral motion will be approximately two feet per revolution, or 1000 feet per minute at 500 r.p.m. Thus, each blade passes laterally through the snow toward the blower at this speed and imparts a corresponding lateral velocity to the snow. Moreover, because of the taper of the blade, it withdraws radially inwardly during its apparent motion, and is believed to leave the snow in free fiight toward the blower along paths parallel to the axis 23 as indicated by the arrows 40 in FIG. 3.

This snow enters both sides of the blower through the brace rings 29 and is picked up by the rapidly rotating paddles 27 to be carried around the impeller and discharged at high velocity into the spout 31. The disk 28 prevents impelled snow from going through the blower toward the opposite end of the scoop. It will be seen that the optimum utilization of the available power in the novel snow thrower, as a result of the novel configuration of the impeller, makes it possible to maintain high speed rotation of the blower for maximum discharge force and capacity.

While the blades are shown as being of constant radial width, it will be evident to those skilled in the art that the width may be varied, for example, to increase the width of the blades progressively toward the center of the impeller while maintaining an overall taper. In addition, more than one helical blade may be provided on each body section for greater capacity, or interrupted blade segments may be staggered around the body sections. Of course, the dimensions stated herein are given only to illustrate one form the snow thrower may take, and larger or smaller forms may be made for different operational capacities.

I claim as my invention:

1. A snow thrower having, in combination, a scoop having an open front defined between laterally spaced upright side walls and adapted to be advanced forwardly along a path to be cleared of snow to feed the snow into 4 the scoop through said open front, an elongated impeller body disposed between said side walls and journaled thereon for rotation about an axis generally perpendicular to said path, said body comprising two sections of frustoconical configuration tapering from both ends of the impeller toward its center, a pair of oppositelyv pitched helical blades wrapped around said sections and having outside diameters tapering axially toward said center, the radial width and axial taper of said blades being correlated to space the outside diameter of each inner convolution of said blades radially inwardly from the inside diameter of the corresponding portions of the next outer convolution and the blades being pitched to impel snow generally axially of said impeller toward said center in said one direction of rotation, and a blower between said sections having open sides for receiving snow from both of said blades and operable to throw the snow out of said scoop.

2. In a snow thrower, the combination of, an openended scoop adapted to be advanced along a path to be cleared of snow, an impeller disposed within said scoop and mounted therein for rotation about an axis extending transversely of said path, said impeller having a body section tapering conically from one side of said scoop toward the other side and a helical blade of substantially constant radial width wrapped around said body section and tapering in outside diameter toward said other side said blade being pitched to impel snow generally axially of said impeller toward said other side in one direction of rotation of the impeller, and means at the smaller end of said body section for receiving snow from said impeller and discharging the snow from said scoop.

3. In a snow thrower, the combination of, a frame adapted to be advanced forwardly along a path to be cleared of snow or other fluent material, and an elongated impeller journaled on said frame for rotation about an axis extending transversely of said path, said impeller having a body with at least one blade thereon of substantially constant radial width for throwing snow generally axially along the impeller toward one end thereof in one direction of rotation of the impeller, both said body and said blade having outside diameters decreasing progressively toward said one end to leave the impelled snow in free flight toward said one end.

4. In a snow thrower, the combination of, an openended scoop adapted to be advanced along a path to be cleared of snow, an impeller disposed within said scoop and mounted therein for rotation about an axis extending transversely of said path, said impeller having a body section tapering from one side of said scoop toward the other side and having a helical blade of generally conical configuration wrapped around said body section and tapering toward said other side, the outside diameter of each convolution of said blade being not greater than the inside diameter of a corresponding portion of a preceding larger convolution, said blade being ptiched for apparent motion toward said other side in one direction of rotation of said impeller thereby to impel snow toward said other side, and means at the smaller end of said body section for receiving snow from said impeller and discharging the snow from said scoop.

References Cited UNITED STATES PATENTS 2,144,316 1/1939 Klauer 37-43 2,419,779 4/ 1947 James 3743 3,078,603 2/1963 Ertsgaard et a1. 37-43 3,230,645 1/1966 Lutz 37-43 X ABRAHAM G. STONE, Primary Examiner.

A. E. KOPECKI, Assistant Examiner. 

